Determining bacterial and host contributions to the human salivary metabolome

TY - JOUR

T1 - Determining bacterial and host contributions to the human salivary metabolome

AU - Gardner, Alexander

AU - Parkes, Harold G.

AU - So, Po-Wah

AU - Carpenter, Guy H.

PY - 2019

Y1 - 2019

N2 - Salivary metabolomics is rapidly advancing. To determine the extent to which salivary metabolites reflects host or microbial metabolic activity whole-mouth saliva (WMS), parotid saliva (PS) and plasma collected contemporaneously from healthy volunteers were analysed by 1H-NMR spectroscopy.Spectra underwent principal component analysis and k-means cluster analysis. Individual metabolites were quantified. WMS samples were cultured on both sucrose and peptide enriched media and correlation between metabolite concentration and bacterial load was assessed. WMS contained abundant short-chain fatty acids (SCFAs) which were minimal in PS and plasma. Spectral profiles of WMS exhibited greater inter-individual variation than those of PS or plasma (6.7 and 3.6 fold, respectively), likely reflecting diversity of microbial metabolomes. WMS bacterial load correlated strongly with SCFA levels. Additional WMS metabolites including amines, amino acids and organic acids were positively correlated with bacterial load. Lactate, urea and citrate appeared to enter the WMS via PS and the circulation. Urea correlated inversely with WMS bacterial load.Oral microbiota contribute significant to the WMS metabolome. Several WMS metabolites (lactate, urea and citrate) are derived from the host circulation. WMS may be particularly useful to aid diagnosis of conditions reflective of dysbiosis. WMS could also complement other gastrointestinal fluids in future metabolomic studies.

AB - Salivary metabolomics is rapidly advancing. To determine the extent to which salivary metabolites reflects host or microbial metabolic activity whole-mouth saliva (WMS), parotid saliva (PS) and plasma collected contemporaneously from healthy volunteers were analysed by 1H-NMR spectroscopy.Spectra underwent principal component analysis and k-means cluster analysis. Individual metabolites were quantified. WMS samples were cultured on both sucrose and peptide enriched media and correlation between metabolite concentration and bacterial load was assessed. WMS contained abundant short-chain fatty acids (SCFAs) which were minimal in PS and plasma. Spectral profiles of WMS exhibited greater inter-individual variation than those of PS or plasma (6.7 and 3.6 fold, respectively), likely reflecting diversity of microbial metabolomes. WMS bacterial load correlated strongly with SCFA levels. Additional WMS metabolites including amines, amino acids and organic acids were positively correlated with bacterial load. Lactate, urea and citrate appeared to enter the WMS via PS and the circulation. Urea correlated inversely with WMS bacterial load.Oral microbiota contribute significant to the WMS metabolome. Several WMS metabolites (lactate, urea and citrate) are derived from the host circulation. WMS may be particularly useful to aid diagnosis of conditions reflective of dysbiosis. WMS could also complement other gastrointestinal fluids in future metabolomic studies.

KW - NMR spectroscopy

KW - metabolomics

KW - oral microbiome

KW - saliva

UR - http://www.scopus.com/inward/record.url?scp=85074126333&partnerID=8YFLogxK

U2 - 10.1080/20002297.2019.1617014

DO - 10.1080/20002297.2019.1617014

M3 - Article

SN - 2000-2297

VL - 11

JO - Journal of Oral Microbiology

JF - Journal of Oral Microbiology

IS - 1

M1 - 1617014

ER -